1. Field of the Invention
The present invention relates to a photomultiplier for multiplying photoelectrons emitted from a photocathode in correspondence with incident light by multilayered dynodes.
2. Related Background Art
Conventionally, photomultipliers have been widely used for various measurement devices in nuclear medicine and high-energy physics such as a .gamma.-camera, PET (Positron Emission Tomography), or calorimeter.
A conventional electron multiplier includes a photomultiplier having a photocathode. This electron multiplier includes an anode and a dynode unit formed by stacking a plurality of stages of dynodes in the incident direction of an electron flow in a vacuum container.